This invention relates to a sorting or ordering circuit or circuit arrangement for sorting three or more inputs, representative of numerical values, into outputs, equal in number to the inputs, with the outputs arranged to represent the numerical values either in the ascending or the descending order. Inasmuch as the descending order is equivalent to the ascending order in this context, the sorting circuit will be described with respect to the ascending order alone. Some of the inputs may have the same value. The wording "the ascending order" is therefore used to mean both monotonously increasing and decreasing orders. According to the number of inputs or outputs, such a circuit is referred to as a two-input-output sorting circuit, a three-input-output sorting circuit, or the like. The inputs and the outputs will be called input values and output values, although such values may be allotted to alphabets and the like so that the inputs and the outputs may represent, for example, the alphabets. Such a sorting circuit is useful, although not restricted, specifically in an electronic data handling system.
As will later be described with reference to one of fifteen figures of the accompanying drawing, it is possible to manufacture a three-input-output sorting circuit by using three two-input-output sorting circuits as sorting units arranged in three stages. A four-input-output sorting circuit is composed of five two-input-output sorting units arranged also in three stages. At any rate, a certain period dependent on the number of binary bits representative of each input or output value is necessary for a two-input-output sorting unit to provide the output values when each value is represented by a time sequence of such binary bits. It takes therefore three periods to sort three or four input values into the output values. For the input values, more than four in number, the time required becomes terrible. The sorting circuit becomes bulky.